The present invention is with respect to a plant for producing enameled wire using an inline process having, for processing wire coming from a wire pay-off system, one after the other a wire drawer, a bare wire annealer, an enamel dope coater, an enamel processing unit and an enameled wire take up unit.
A plant designed on these general lines is to be seen in British Pat. No. 1,305,032 or the parallel German specification 2,058,151. In the case of this inline plant the wire coming from the wire drawer makes its way over guide rollers through a tempering unit or annealer, where it is annealed for freeing it of stresses, that is to say normalized, before running into an enameling system, as the next part of the plant, in which the wire is given a number of coatings of enamel dope which is then baked.
Even although this form of inline process may be looked upon as giving useful effects in view of continuously automated wire processing systems, because, as well as other useful effects, the production rate is increased and costs lowered while the quality of the wire produced is better than in the prior art, there are a number of shortcomings in connection with the process, more specially in connection with a higher power need, undesired effects on the environment caused by chemicals from the plant. Suggestions for better designs have been made more specially in connection with the enameling system, such suggestions being more importantly in connection with cutting down the power need in this system and sealing off the wire inlets and outlets. For example a suggestion has been made in the past for burning solvent vapors and products of cleavage in an output catalyst unit, such vapors and products being produced when the bare wire, heated by radiant heaters is coated with the dope. When such burning takes place the heated air produced may be used for drying and curing the dope coating on the wire. One useful effect of catalytic burning or combustion is that the energy of the solvents may be used for drying the dope coating and baking it, while on the other hand the amount of undesired chemicals given off into the environment is cut back.
However, because the need for saving power is becoming more and more important and laws made by public authorities for protection of the environment are becoming tighter and harder to keep to, such suggestions do not go far enough. Furthermore these suggestions do not take into account the question of space taken up by the plant.